New York State Department of Environmental Conservation (NYSDEC) Pesticide Practice Exam

Cholinesterase is an enzyme in the body that plays a critical role in the functioning of the nervous system. Specifically, it helps break down acetylcholine, a neurotransmitter involved in transmitting signals between nerve cells, particularly in muscle movement and respiratory function.

When someone is exposed to certain types of pesticides, particularly organophosphates and carbamates, these chemicals can inhibit cholinesterase activity. This inhibition leads to an accumulation of acetylcholine, which overstimulates the nervous system. One of the severe consequences of this overstimulation is respiratory distress, which can result in the inability to breathe. As the muscles responsible for respiration are affected, respiratory failure can occur, making this a serious and potentially life-threatening effect of pesticide exposure.

In contrast, the other choices do not relate to the well-documented effects of cholinesterase inhibition caused by pesticide exposure. Improved cognitive function and increased muscle coordination are contradictory to the effects of such exposure, which typically leads to confusion, muscle twitching, and weakness. Chronic fatigue may be observed in various scenarios but is not directly linked to cholinesterase inhibition in the context of pesticide exposure.